Rev. Thomas Espin discovered IC 2157, along with IC 2156, visually on 11 Jan 1899 with his 17.3-inch reflector at his private observatory in Durham, England.

400/500mm - 17.5" (3/8/97): at 220x, ~30 stars are visible in a 6' group, including a half-dozen brighter mag 10.5-12 stars. The densest portion is ~4' diameter tapering to the NW and appears fairly rich with averted (over resolved haze). The east end of group is formed by a 5' arc of mag 10-12 stars concave to the NW. Forms a pair with the IC 2156 group 6' N (possibly part of IC 2157). Located ~35' W of NGC 2158 (off the SE side of M35).

Notes by Steve Gottlieb